using System;

namespace euler1
{
	public class Euler1
	{
		public static void Main ( string[] args )
		{
			int sum = 0;

			for ( int i=3; i < 1000; i++ )
			{
				if ( i%3 == 0 || i%5 == 0 )
				{
					sum += i;
				}
			}

			Console.WriteLine (sum);
		}
	}
}

